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Ramli Nazir Hossein Moayedi Rozaimi Bin Mohd Noor Soheil Ghareh 《Arabian Journal of Geosciences》2016,9(20):741
The attenuation equation for far field earthquake is important because the earthquake occurring in neighboring countries can be felt in Malaysia. In this study, a new attenuation was generated using the regression method. It was developed to calculate the peak ground acceleration (PGA) onsite (offshore platform). The database consisting of more than 150 PGAs from 9 events of earthquakes recorded by the Seismology Station in Malaysia was used to develop the relationship. In addition, attenuation relationships for subduction mechanisms from previous researchers are then compared with the newly generated ones in this research. The new attenuation equation was also validated and used to calculate the acceleration for far field earthquake in a case study of offshore platform at a Terengganu seaside. The result of PGA from the new generated attenuation relationship was in a good match with previous attenuation equations. 相似文献
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GeoJournal - This study is an attempt to carry landslide susceptibility assessment along national highway 1D a lifeline to the Ladakh region using Frequency Ratio Method in GIS environment. The... 相似文献
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Middle Jurassic Coptoclavidae (Insecta:Coleoptera:Dytiscoidea) from China:a Good Example of Mosaic Evolution 总被引:2,自引:2,他引:0
<正>Adults of the aquatic coptoclavid beetles(Coleoptera:Adephaga:Dytiscoidea),described from four Middle Jurassic fossil localities in Inner Mongolia and Liaoning in northeastern China,are attributed to Daohugounectes primitives Wang,Ponomarenko and Zhang,2009,which was previously proposed after study of larvae.The generic name Timarchopsis Brauer,Redtenbacher and Ganglbauer,1889 is proposed as a substitute for the preoccupied and junior homonym Necronectes Ponomarenko,1977,non Milne-Edwards,1881. Furthermore,the subfamily name Necronectinae Ponomarenko,1977 is substituted by the available name Timarchopsinae.Daohugounectes is placed into Timarchopsinae because its adults have long,slightly apically widened tibiae and small femoral plates.The adults of this genus differ from those of other Timarchopsinae in the following features:antennae short and widened in the middle part;basal segments of protarsi not cut apically; metaventrite with a triangular plate.The larvae look like somewhat primitive forms in the subfamily Timarchopsinae.In contrast to these primitive larvae,the adults with some advanced characters can be regarded as among the most advanced forms in the subfamily Timarchopsinae,and probably represent a transition between the Timarchopsinae and Charanoscaphinae.Such mosaic evolution within Daohugounectes indicates that the evolutionary process of aquatic beetles is far more complex than previously thought. 相似文献
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Shafi Noor ISLAM 《Frontiers of Earth Science》2010,4(4):438-448
Wetlands constitute a part of human heritage. It has played a significant role in the development of human culture and society.
More over it contains very rich components of biodiversity of local, national, and regional significance. They also provide
habitat for a variety of resident and migratory waterfowl, a significant number of endangered species, and a large number
of commercially important species. Mangrove wetlands are unique environments of floral-faunal assemblages, providing a complex
detritus-based food-web for a number of marine and brackish water organisms. Wetlands in Bangladesh have great importance
for the country’s economic, industrial, ecological, socioeconomic, and cultural aspects. There are five types of wetlands
available in Bangladesh, such as saltwater wetlands, freshwater wetlands, palustrine wetlands, lacustrine wetlands, and manmade
wetlands. There are 43 designated wetlands, and some are under threat from indiscriminate utilization, encroachments and reclamation,
urbanization and drawbacks from agricultural development, and flood control. Almost 50% of the country’s people are directly
dependent on wetlands resources. The vast majority of the poor people in the wetlands areas are dependent on wetlands resources
for their nourishment. Wetlands have potential and have been recognized as a driving force for biodiversity conservation and
rural socioeconomic improvement. Smart-use of wetlands can solve the ecosystems problems in the floodplain areas. A comprehensive
analysis of the various issues leading to wetlands degradation is made in this study. The country needs an adequate interdisciplinary
policy and political will to implement it for sustainable management and protection of wetlands and ecologically sensitive
ecosystems in Bangladesh. Therefore, a reliable data bank is provided in this study to enhance the conservation measures initiated
by the Government. 相似文献
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The Influence of the North Atlantic Oscillation on Rainfall Triggering of Landslides near Lisbon 总被引:1,自引:0,他引:1
Ricardo?M.?TrigoEmail author José L.?Zêzere Maria?L.?Rodrigues Isabel?F.?Trigo 《Natural Hazards》2005,36(3):331-354
The majority of landsliding episodes in the area north of Lisbon are associated with rainfall events of short (less than 5
days) medium (5–20 days) or long duration (more than 20 days). The precipitation regime in Portugal is highly irregular, with
large differences between wet and dry years. We have assessed the impact of the North Atlantic Oscillation (NAO) on both the
winter precipitation and the timing and magnitude of associated landslide events. Results show that the large inter-annual
variability of winter precipitation is largely modulated by the NAO mode. The precipitation composite corresponding to high
NAO index presents a considerable lower median value (47 mm/month) than the corresponding low NAO index class (134 mm/month).
The entire precipitation distribution associated with the low NAO index composite encompasses a wider range of values than
the corresponding high NAO index composite. This non-linear behavior is reflected in the probability of occurrence of a very
wet month (precipitation above the 90% percentile) that is just 1% for the positive NAO class and 23% for low NAO index months.
Results for the low NAO class are crucial because these months are more likely associated with long-lasting rainfall episodes
responsible for large landslide events. This is confirmed by the application of a 3-month moving average to both NAO index
and precipitation time series. This procedure allowed the identification of many months with landslide activity as being characterized
by negative average values of the NAO index and high values of average precipitation (above 100 mm/month). Finally, using
daily data we have computed the return periods associated with the entire set of landslide episodes and, based on these results,
obtained a strong linear relationship between critical cumulative rainfall and the corresponding critical rainfall event duration. 相似文献
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Acta Geotechnica - This technical paper focuses on evaluating the shear strength of unsaturated sand at drying, wetting and alternate drying–wetting cycles, as well as the correlation between... 相似文献